Centrifugal pump structure

ABSTRACT

A tube progressively decreases in sectional area from an inlet to an outlet while spiraling outwardly. The tube is affixed within a bell rotatable on a housing which has an intake chamber adjacent the tube inlet. A shaft journalled on the housing drives the bell. The slope of the tube relative to an axial plane through the shaft progressively increases from inlet to outlet. The outlet opens into an annular passageway defined by the bell and housing and having a discharge opening for pumped fluid.

11mm States [Patent [191 Banyai 51 May 7,1974

[ CENTRIFUGAL PUMP STRUCTURE [76] Inventor: Albert Banyai, 12353Wyoming,

Detroit, Mich. 48204 [22] Filed: July 5, 1973 [21] Appl. No.: 376,801

[52] US. Cl. 415/88, 415/73 [51] Int. Cl. F04d l/04, F04d 1/12, F04d1/14 [58] Field of Search 415/88, 89, 71, 73, 75;

[56] References Cited UNITED STATES PATENTS 1,074,043 9/1913 Breverm,..415/88 1,921,720 4/1932 Anderson ..4l5/88 FOREIGN PATENTS ORAPPLICATIONS 4,058 3/1900 Great Britain 415/88 Primary Examiner-CarltonR. Croyle Assistant ExamineF-Louis J. Casaregola Attorney, Agent, orFirmArthur Raisch [5 7] ABSTRACT A tube progressively decreases insectional area from .an inlet to an outlet while spiraling outwardly.The tube is affixed within a bell rotatable on a housing which hasanintake chamber adjacent the tube inlet. A shaft journalled on thehousing drives the bell. The slope of the tube relative to an axialplane through the shaft progressively increases from inlet to outlet.The

outlet opens into an annular passageway defined by the bell and housingand having a discharge opening for pumped fluid. v

16 Claims, 3 Drawing Figures This invention relates to a centrifugalpump. The conventional centrifugal pump comprises a shaft with generallyradial impeller blades mounted thereon, the shaftbeing rotatably mountedon a housing so that the blades tum within a chamber in the housing. Thefluid to be pumped is drawn axially inwardly through .a generallycentral inlet and is forced radially outwardly to an outlet by theimpeller blades. This results in an abrupt change of direction of thefluid being pumped and a consequent loss of efficiency. In addition,when the pumped fluid is a liquid, the abrupt change of direction tendsto cause cavitation resulting in furtherinefflciency. g

The object of the present invention is to provide a relativelysimplepump structure improved to eliminate the above-mentioned inefficienciesand further improved to increase efficiency by controlling the directionof flow of the fluid discharging from the pump. One form of theinvention is shown in the accompanying drawings.

FIG. 1 is a partly diagrammatic view of a pump according to theinvention shown partly in section and partly in elevation.

FIG. 2 is a sectional view on line 22 of FIG. ll.

FIG. 3 is a sectional view on line 3-3 of FIG. 1.

Shown in the drawings is a pump according to the invention having a body12 which includes a base 14, a housing 16, and a cap 18. Base 14 andhousing 16 are secured together by suitable means such asflanges 20 and22 respectively thereon anchored to each other by bolting (not shown).Similarly, cap 18 is secured to housing 16 by suitable means such asflanges 24 and 26 respectively thereon anchored to each other by bolting(not shown). Pump 10 may be supported on a mount 28 by engaging baseflange 20 on the mount.

Base 14 has an intake pipe 30 adapted for connection to a pipe or hose32 which extends to a source of fluid to be pumped. Intake pipe 30 opensinto an intake chamber 34 in base 14. A generally bell-shaped rotor 36has a small end 38 rotatably supported by a shoulder 40 on base 14through an interposed bearing structure 42. Rotor 36 has a larger end 44spaced radially inwardly of a skirt 46 on cap 18. Large end 44 isprovided with a closure 48 slightly spaced from cap 18 as at 50.

Rotor 36 is driven by a shaft 52 journalled on base 14 at 54 on cap 18at 56. A suitable drive connection is provided between shaft 52 androtor 36 which may comprise, for example, a spline connection'58 betweenthe shaft and a central hub 60 on closure 50. Shaft 52 extends centrallythrough rotor 36 and its smaller end 38 and through intake chamber 34.O-ring seals 62,63 and 64 are provided between the shaft and base 14,hub 60 and cap 18 respectively. A sea] 65 is provided adjacentthejuncture of small end 38 of rotor 36, housing 16 and bearing structure42. Shaft 52 is driven by suitable means such as a belt 66 entrainedaround a pulley 68 thereon and around the output pulley of a motor.

At least one impeller tube 70 is mounted within rotor 36. Tube 70 has anupstream end portion 72 affixed to the smaller end 38 of rotor 36 andhas a downstream end portion 74 affixed to a generally axially extendingportion 76 of rotor 36 adjacent larger end 44. Upstream end portion 72defines an inlet 78 and downstream end portion 74 defines an outlet 80.Inlet 78 opens into intake chamber 34 and outlet 80 opens into anannular chamber 82 defined by housing flange 24, cap skirt 46, andportions 44,76 of rotor 36. Chamber 82 is provided with a discharge pipe84 for the pumped fluid. Except for inlet 78 and outlet 80 the ends ofrotor 36 are isolated from chambers 34 and 82 by suitable seals toprevent pumped fluid from entering the rotor outsideof tube 70.

' Tube has the general shape of a spiral between its inlet 78' andoutlet 80. Upstream end portion 72 is located radially closely adjacentshaft 52. Progressing angularly and axially downstream from the inletthe following variations in the tube occur: the radialdistance of thetube from the shaft progressively increases to a maximum at outlet theslope of the tube relative to an axial plane through shaft 52progressively increases to a maximum at outlet 80; and the effectivesectional area of the tube progressively decreases, preferablyuniformly, to a minimum at outlet 80.

Tube 70 turns' through an angle of at least 180 between inlet 78 andoutlet 80. Theslope of the tube at outlet 80-relative to an axial planethrough shaft 52 is preferably in the range from about 70 to about Theaxis of the tube at outlet 80 is disposed rearwardly with respect to thedirection of rotation of rotor 36 for a purpose to be described. Theradially outer surface portions of tube 70 are engaged against theinterior sur+ face of the wall defined by bell-shaped rotor 36.

In use, let it be assumed that pump 10 has been primed by filling pipe32, intake pipe 30, intake chamber 34, and tube 70 with the fluid to bepumped to a level slightly above inlet 78. The motor connected with belt66 is set into operation for rotating pulley 68, shaft 52, and rotor 36together with tube 70 in a clockwise direction as the drawings areviewed. Because of the slope of lower portion 72 of the tube the fluidis forced outwardly and axially away from inlet 78 by centrifugal force,which force progressively increases as the fluid moves downstreambecause of the progressively increasing radial distance of the tube fromshaft 52. The centrifugal force reaches its maximum adjacent outlet 80.

The body of water moving within the tube gradually changes directionbecause of the progressive change in slope of the tube and at outlet 80the fluid flows at an abrupt angle to an axial plane through shaft 52 asbest seen in FIG. 1. Also, the velocity of flow of the fluid in the tubeincreases to a maximum at outlet 80 because of the progressivelydiminishing sectional area of the tube. The fluid is discharged intoannular ring 82 and then through discharge pipe 84 at high kineticenergy. Since the fluid is forced out of outlet 80 in a directiongenerally opposite to the direction of rotation of rotor 36, thereaction thereto assists rather than resisting the motor effort ofrotation of the rotor.

The gradual change of direction of the flowing body of fluid, thegradual increase of centrifugal force thereon, and the gradualacceleration of the fluid in passing through tube 70 decreases thetendency toward cavitation of pumped liquid and together with the propulsion effect of the water exiting from outlet 80 contributes tooverall efficiency of the pump.

The wall of rotor 36 supports tube 70 against the centrifugal forceexerted thereon.

For purposes of clarity and simplicity of illustration pump 10 has beenillustrated as having only one tube 70. Such a pump would operatesatisfactorily though it as comprising a single integral body. Anexperimental working model of pump in-fact has this structure. However,in commercial models bell 36 and tube 70 will likely comprise separateelements secured together at appropriate locations such as adjacentinlet 78 and 'outlet 80 by bolting or the equivalent and the use offluid tight seals where required.

It is belived that a typical commercial pump 10 according to thisinvention will have three tubes 70 each with an inlet 78 diameter ofabout 4% inches, an outlet 80 diameter of about one inch, the radialdistance from the axis of shaft 52 to the neutral axes respectively ofinlet 70 and outlet 80 being about 4% inches and 12 inches, the axiallength of tube 70 being about 19 inches, the tube turning through about360 and varying in slope relative to an axial plane through shaft 52cording to my calculations a pump 10 so constructed can be turned at5,000 rpm by a 5 horse power motor and at that rate of operation willpump theoretically as much as 5,600gallons of water per minute, ortaking into consideration resistance factors not yet determined throughexperimentation, about 2,800 gallons per minute. The pump can beproduced in different sizes tomeet various capacity requirements.

I claim:

l. Centrifugal pumpstructure which comprises,

a body, a shaft rotatably mounted on said body, a tube, and meansforming a driving connection through ,which'said tube is rotated by saidshaft,

said body having a chamber adapted to receive fluid to be pumped,

said tube having an inlet adjacent one end open to said chamber, saidinlet having a relatively large effective area and being locatedrelatively closely to said shaft,

said tube having an outlet adjacent its other end which is spaced fromsaid inlet in a direction axial of said shaft,

said outlet having a rleatively small effective area and being locatedradially farther from said shaft than said inlet,

said tube, progressing from said inlet toward said outlet, having aneffective sectional area which progressively decreases, having a sloperelative to an axial plane through said shaft which progressivelyincreases, and having a radial distance from said shaft whichprogressively increases.

2. The structure defined in claim 1 wherein said tube has the generalshape of a spiral which, progressing from said inlet toward said outlet,turns in a direction opposite to its direction of rotation bysaid-shaft.

'3. The structure defined in claim 2 wherein said spiral turns throughat least 180, said slope adjacent said outlet being in the range ofabout 70 to about 90.

4. The structure defined in claim 3 wherein said spiral turnsthroughabout 360, said slope adjacent said outlet being about 90. e

5. The structure defined in claim 3 wherein said outlet faces generallyin said opposite direction.

6. The structure defined in claim 1 wherein said driving connectioncomprises a generally bell-shaped element mounted on said shaft forrotation therewith, said element having a wall with interior surfaceportions shaped complementally to exterior surface portions of saidtube, said tube being affixed within said element with said surfaceportions interengaged.

7. The structure defined in claim 6 wherein said element supports saidtube against centrifugal force exerted thereon incidental to operationof said pump structure.

8; The structure defined in claim 7 wherein said inlet opens generallylongitudinally through a smaller end of said element into said chamber,said outlet opening laterally through a circumferentially extendingportion of said wall adjacent the larger end of said element.

9. The structure defined in claim 8 wherein said element is rotatablysupported on said body through a bearing with said smaller end adjacentsaid chamber.

10. The structure defined in claim 9 wherein said body defines a'housing around said element, portions of said housing and elementcooperating to define a closed hollow ring around said circumferentiallyextending portion of said wall into which pumped fluid discharges fromsaid outlet, said ring having a discharge opening.

11. The structure defined in claim 10 wherein said cooperating portionsof .said body and element include a closure for the larger end of saidelement, a cap on said body overlying but spaced from said closure, saidcap extending radially outwardly of said element and having an annularskirt spaced radially outwardly of said circumferentially extendingportion of said wall.

12. The structure defined in claim 11 wherein said shaft is journalledon said cap, extends through said closure, element and chamber, and isjournalled on said body adjacent said chamber.

13. The structure defined in claim 12 wherein said body, between saidbearing and said ring, is shaped generally complementally to but spacedfrom said element.

14. The structure defined in claim 13 wherein a fluidtight seal isprovided between the smaller end of said element and said body.

15. The structure defined in claim 1 wherein a plurality of said tubesare symmetrically arranged around said shaft, each having a said drivingconnection therewith.

16. The structure defined in claim 1 wherein said sectional areadecreases substantially uniformly.

1. Centrifugal pump structure which comprises, a body, a shaft rotatablymounted on said body, a tube, and means forming a driving connectionthrough which said tube is rotated by said shaft, said body having achamber adapted to receive fluid to be pumped, said tube having an inletadjacent one end open to said chamber, said inlet having a relativelylarge effective area and being located relatively closely to said shaft,said tube having an outlet adjacent its other end which is spaced fromsaid inlet in a direction axial of said shaft, said outlet having arleatively small effective area and being located radially farther fromsaid shaft than said inlet, said tube, progressing from said inlettoward said outlet, having an effective sectional area whichprogressively decreases, having a slope relative to an axial planethrough said shaft which progressively increases, and having a radialdistance from said shaft which progressively increases.
 2. The structuredefined in claim 1 wherein said tube has the general shape of a spiralwhich, progressing from said inlet toward said outlet, turns in adirection opposite to its direction of rotation by said shaft.
 3. Thestructure defined in claim 2 wherein said spiral turns through at least180*, said slope adjacent said outlet being in the range of about 70* toabout 90*.
 4. The structure defined in claim 3 wherein said spiral turnsthrough about 360*, said slope adjacent said outlet being about 90*. 5.The structure defined in claim 3 wherein said outlet faces generally insaid opposite direction.
 6. The structure defined in claim 1 whereinsaid driving connection comprises a generally bell-shaped elementmounted on said shaft for rotation therewith, said element having a wallwith interior surface portions shaped complementally to exterior surfaceportions of said tube, said tube being affixed within said element withsaid surface portions interengaged.
 7. The structure defined in claim 6wherein said element supports said tube against centrifugal forceexerted thereon incidental to operation of said pump structure.
 8. Thestructure defined in claim 7 wherein said inlet opens generallylongitudinally through a smaller end of said element into said chambEr,said outlet opening laterally through a circumferentially extendingportion of said wall adjacent the larger end of said element.
 9. Thestructure defined in claim 8 wherein said element is rotatably supportedon said body through a bearing with said smaller end adjacent saidchamber.
 10. The structure defined in claim 9 wherein said body definesa housing around said element, portions of said housing and elementcooperating to define a closed hollow ring around said circumferentiallyextending portion of said wall into which pumped fluid discharges fromsaid outlet, said ring having a discharge opening.
 11. The structuredefined in claim 10 wherein said cooperating portions of said body andelement include a closure for the larger end of said element, a cap onsaid body overlying but spaced from said closure, said cap extendingradially outwardly of said element and having an annular skirt spacedradially outwardly of said circumferentially extending portion of saidwall.
 12. The structure defined in claim 11 wherein said shaft isjournalled on said cap, extends through said closure, element andchamber, and is journalled on said body adjacent said chamber.
 13. Thestructure defined in claim 12 wherein said body, between said bearingand said ring, is shaped generally complementally to but spaced fromsaid element.
 14. The structure defined in claim 13 wherein afluid-tight seal is provided between the smaller end of said element andsaid body.
 15. The structure defined in claim 1 wherein a plurality ofsaid tubes are symmetrically arranged around said shaft, each having asaid driving connection therewith.
 16. The structure defined in claim 1wherein said sectional area decreases substantially uniformly.